[clang] [C++26] [Contracts] Initial parser support (PR #221139)

[Chuanqi Xu via cfe-commits]

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@@ -4244,6 +4222,142 @@ void Parser::ParseTrailingRequiresClause(Declarator &D) {
   }
 }
 
+std::optional<Parser::ContractSpecifierKind>
+Parser::getContractSpecifierKind() {
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ChuanqiXu9 wrote:

Yeah, but `Tok` is a member variable and other functions did this style (use Tok directly)

https://github.com/llvm/llvm-project/pull/221139